1. Field
The described technology relates to systems and methods of compensating for performance variation of electronic circuits caused by temperature changes.
2. Description of the Related Technology
Automatic Test Equipment (ATE) is a computer based system that tests a device, known as a Device Under Test (DUT). The ATE can be programmed to provide power signals, reference signals, and input signals to the DUT. The ATE can also be programmed to receive signals, such as voltages and currents, generated by the DUT in response to the input from the ATE. The ATE can compare the received signals with predetermined values to determine whether the DUT is operating according to specifications. Testing and diagnosing faults with ATE can be performed on wafer die, packaged electronic parts, or electronic systems.
In order for the ATE to generate signals for the DUT and to receive and compare signals from the DUT, the ATE extensively uses reference voltages. The reference voltages are generally internal to the ATE and are used by the circuitry of the ATE to generate reference signals and input signals for the DUT, and to receive and compare output signals from the DUT. Accordingly, accurate reference voltages are very important to the proper function of the ATE.
In general, the circuitry of the ATE and the circuitry used to generate the reference voltages have performance which is sensitive to temperature. This may be especially problematic because the temperature within the ATE can vary dramatically with, for example, changing ambient conditions and changing power used in various components of the ATE which change during its operation. Accordingly, voltages, currents, propagation delays, and other circuit parameter values change during the operation of the ATE. The temperature dependence of ATE performance can be a dominant source of ATE inaccuracy.